Re: [Qemu-devel] [PATCH v5 12/20] disas: nanoMIPS: Clean up handling of 16-bit logic instructions

[Aleksandar Rikalo]

> From: Aleksandar Markovic
> Sent: Thursday, December 27, 2018 2:18 PM
> To: Aleksandar Markovic; address@hidden; Aleksandar Rikalo
> Cc: address@hidden; Stefan Markovic
> Subject: Re: [PATCH v5 12/20] disas: nanoMIPS: Clean up handling of 16-bit 
> logic instructions
>
> > From: Aleksandar Markovic <address@hidden>
> > Subject: [PATCH v5 12/20] disas: nanoMIPS: Clean up handling of 16-bit 
> > logic instructions
>
> > Clean up handling of 16-bit logic nanoMIPS instructions:
>
> ...
> >
> > -    return img::format("AND %s, %s", rs3, rt3);
> > +    return img::format("AND[16] %s, %s", rs3, rt3);
> > }
>
> I wonder if this instruction should be displayed with two or three arguments 
> (by design of this instruction, the
> destination is the same register as one of sources, but would it be more 
> clear for end user to see three arguments,
> even if two of them are always the same?)

nanomips-linux-musl-objdump always shows three registers and generic mnemonic 
AND (without [16]).
On the other hand, inline assembler accepts syntax with two registers or/and 
instruction format specification.

We should decide whether we should follow objdump or assembler conventions.
In any case, the same rule should be applied consistently across this 
disassembler.

Thanks,
Aleksandar Rikalo

>
> Aleksandar
>